This invention relates in general to vehicle brake assemblies and in particular to an improved structure for a ball nut assembly for an electromechanically actuable parking brake assembly of a brake assembly.
Most vehicles are equipped with a brake system for slowing or stopping movement of the vehicle in a controlled manner. A typical brake system for an automobile or light truck includes a disc brake assembly for each of the front wheels and either a drum brake assembly or a disc brake assembly for each of the rear wheels. The brake assemblies are actuated by hydraulic or pneumatic pressure generated when an operator of the vehicle depresses a brake pedal.
The structures of these drum brake assemblies and disc brake assemblies, as well as the actuators therefor, are well known in the art. For example, the disc brake assembly may be a “drum-in-hat” type of disc brake assembly having an emergency or parking brake actuated by an electric actuator unit, such as disclosed by U.S. Pat. No. 8,011,482 to Boyle et al., the disclosure of which is hereby incorporated by reference in entirety herein. Alternatively, the disc brake assembly may have an electric emergency or parking brake actuated by an electric actuator unit, such as disclosed by U.S. Pat. No. 6,767,305 to Backes et al. or U.S. Pat. No. 8,684,147 to Winkler et al., the disclosures of which are hereby incorporated by reference in entirety herein.
Typically, the electric actuator unit employs a ball nut assembly for use in actuating the emergency or parking brake. However, available packaging space for the ball nut assembly is limited in order to maximize vehicle occupant space. Thus, it would be desirable to reduce packaging space required for the ball nut assembly of the electric actuator unit for the electromechanically actuable parking brake assembly of a disc brake assembly.